From: Jason Etheridge <jason@esilibrary.com>
Date: Tue, 4 Sep 2018 05:38:35 +0000 (-0400)
Subject: migration_tools.handle_link3_skip_null
X-Git-Url: http://git.equinoxoli.org/?p=migration-tools.git;a=commitdiff_plain;h=966be9cbd02aefdb801f60f9158d15de013f88b1

migration_tools.handle_link3_skip_null

Signed-off-by: Jason Etheridge <jason@esilibrary.com>
---

diff --git a/sql/base/base.sql b/sql/base/base.sql
index f302b44..2907444 100644
--- a/sql/base/base.sql
+++ b/sql/base/base.sql
@@ -3939,6 +3939,49 @@ CREATE OR REPLACE FUNCTION migration_tools.handle_link3 (TEXT,TEXT,TEXT,TEXT,TEX
 
     END;
 $$ LANGUAGE PLPGSQL STRICT VOLATILE;
+
+CREATE OR REPLACE FUNCTION migration_tools.handle_link3_skip_null (TEXT,TEXT,TEXT,TEXT,TEXT,TEXT,TEXT) RETURNS VOID AS $$
+    DECLARE
+        table_schema ALIAS FOR $1;
+        table_a ALIAS FOR $2;
+        column_a ALIAS FOR $3;
+        table_b ALIAS FOR $4;
+        column_b ALIAS FOR $5;
+        column_w ALIAS FOR $6;
+        column_x ALIAS FOR $7;
+        proceed BOOLEAN;
+    BEGIN
+        EXECUTE 'SELECT EXISTS (
+            SELECT 1
+            FROM information_schema.columns
+            WHERE table_schema = $1
+            AND table_name = $2
+            and column_name = $3
+        )' INTO proceed USING table_schema, table_a, column_a;
+        IF NOT proceed THEN
+            RAISE EXCEPTION '%.% missing column %', table_schema, table_a, column_a; 
+        END IF;
+
+        EXECUTE 'SELECT EXISTS (
+            SELECT 1
+            FROM information_schema.columns
+            WHERE table_schema = $1
+            AND table_name = $2
+            and column_name = $3
+        )' INTO proceed USING table_schema, table_b, column_b;
+        IF NOT proceed THEN
+            RAISE EXCEPTION '%.% missing column %', table_schema, table_b, column_b; 
+        END IF;
+
+        EXECUTE 'UPDATE ' || quote_ident(table_b) || ' b'
+            || ' SET ' || quote_ident(column_x) || ' = ' || quote_ident(column_w) || ' FROM ' || quote_ident(table_a) || ' a'
+            || ' WHERE a.' || quote_ident(column_a)
+            || ' = b.' || quote_ident(column_b)
+            || ' AND a.' || quote_ident(column_w) || ' IS NOT NULL';
+
+    END;
+$$ LANGUAGE PLPGSQL STRICT VOLATILE;
+
 -- convenience function for handling desired asset stat cats
 
 CREATE OR REPLACE FUNCTION migration_tools.vivicate_asset_sc_and_sce (TEXT,TEXT,TEXT,TEXT) RETURNS VOID AS $$